Wireless telephones are popular, ubiquitous devices. It is now possible to make and receive phone calls from almost any place in the world. Communication is even possible from remote and undeveloped areas using wireless satellite telephones. Herein, the term wireless telephone refers to any device capable of transmitting and receiving voice and/or data (non-voice) information to and from a network without the use of wires, cables, or other tangible transmission media. So-called cellular telephones are a common example of wireless phones.
Wireless telephones and the networks by which they communicate operate according to various technologies, including analog mobile phone service (AMPS), circuit switching, packet switching, wireless local area network (LAN) protocols, code division multiple access (CDMA), time division multiple access (TDMA), frequency-division multiplexing (FDM), spread-spectrum, global system for mobile communications (GSM), high-speed circuit-switched data (HCSD), general packet radio system (GPRS), enhanced data GSM environment (EDGE), and universal mobile telecommunications service (UMTS). Of course, these are only examples, and other technologies may be employed in wireless communication as well.
Herein, the term ‘wireless device’ is meant to include wireless telephones (including cellular, mobile, and satellite telephones), and also to include a variety of other wireless devices, including wireless web-access telephones, automobile, laptop, and desktop computers that communicate wirelessly, and wireless personal digital assistants (PDAs). In general, the term ‘wireless device’ refers to any device with wireless communication capabilities.
Many companies produce wireless telephones and other wireless devices. Among the more well-known producers are Nokia®, Ericsson®, Motorola®, Panasonic®, Palm® Computer, and Handspring®. A variety of producers also provide wireless devices comprising versions of the Microsoft® Windows® operating software.
Third generation (3G) wireless devices provide high-bandwidth wireless access to communication networks. With such devices it may be possible to provide services to wireless devices such as streaming video, multimedia messaging, and so forth. Users of the network may, at different times, employ different devices to access the network. The quality and availability of services may vary according to the capabilities of the device employed for access, the access device's present operating environment, and other dynamic parameters.